| 摘要 |
A circuit for providing controlled pulses of direct current to vary the speed of a direct current motor. A main controlled rectifier applies current to the motor. A commutation circuit consisting of an inductor, a capacitor and another controlled rectifier turns off the main controlled rectifier by reversing its polarity. Another circuit, referred to as a "ring-around" circuit, consisting of another inductor and controlled rectifier reverses the polarity of the commutating capacitor preparatory to the commutation of the main controlled rectifier. |
